Forming die



` Filed Feb. 18, 1946 2 2 4 z2 [2f )(25 LV; l L l z'gf-lmhw 5 m *jig-:ETL L y mg 6 z2 46 2z NUM WWU. C@ MMT 3 (4.5 A5 [am p-Td L 22 2/ Mij/19.2 22 4 June 20, 1950 c. LEDEL 2,512,161

FORMING DIE 2 Sheets-Sheet 1 ///nm\///MsQ/Z5///////fw//// y y WIE ,Fel

INVENToR. fz Zfaa June 20, 1950 c. LEDEL 2,512,161

FORMING DIE I Filed Feb. 18, L94@ 2 Sheets sh.et 2

I 4 11.2. lL/ 257// 45 U37/ I N V EN TOR. 62a [50a @w d m K fifa/726,15

Patented June 20, 1950 y UNITED STATES P'flf'l-TA ,OFFICE FORMINGDIE v Carl Ledel, Los Angeles, Calif., assi'ginor of" ones third to Peter Rice and onefth'ird to Sani Schuster, both of Los Angeles, Calif. Application l'ebruaryA 18, 1946, Serial Nm648,3"29v 4 Claims.

rI'his invention relates to improvements in forming dies utilized in forming stampi-rigs or metal blanks into desired shapes by bending portions of the stain-pings or blanks relative to other portions thereof.

An object of the invention is to provide an improved forming die which can be easily and economically constructed and assembled and which will efciently bend and 'shape a stamping or blank accurately and without scarring or otherwise detrimentally effecting the surface of the metal.

More specifically, an object of the invention is to provide an improved forming die wherein there are male and female die elements with the female die element equipped with a form ing head adapted to telescope over the male die or punch and which is backed by a compressi-ble material adapted to be squeezed laterally on engagement of the head with the base of the male die to squeeze or press the metal of the stamping or blank laterally into the desired position. All metals used in doing this class of work possess some inherent spring back and if, for example, a at stamping is to have flanges or its side edges bent downwardly at right angles to the plane of the stamping it is necessary to undercut the sides of the punch or male die and to press the downwardly bent flange portions or side edge portions inwardly against these undercut sides oi the punch so that on allowing for the spring back these portions after springing back will assume their desired positions exactly at right angles to the plane of the body of the stamping.4 By the improved die the compressible material that backs the head on the female die becomes squeezed and pressed laterally during the final closing movements of the die and provides a means for simply and automatically applying lateral pressure to the sides of the stamping to press them inwardly against the undercut sides of the punch or male die. This pressure is automatically released on opening the parts of the die.

Another object of the invention is to provide av forming die having the above-described characteristics wherein the head on the female die is so mounted as to be susceptible of some lateral movement as well as vertical movement that is required to compress the compressible material. By having the head thus floating with respect to the female die it may adjust itself with relation to the punch or male die. The amount of lateral movement need not be great as ordinarily only' wise detrimentally eifect the surface of the metal stamping.

2. vWith the foregoing and other' objects View; which will be. made manifest inthe following' detailed description and specically pointed A`out in the appended claims, reference is had t'o the accompanying'drawings' for an illustrative einev bodiinent o f the invention, wher-'emi Figure risa viewl in side elevation of the proved forrriing die embodying the .present in`"' ventio'ri;

Fig. 2 is a bottom plan view of the female part of the dieormay be regarded as a horizontal section taken substantially upon Ythe line 2'-2` upon Fig. 1 in the direction indicated;

Fig. 3j is a top plan view'of the male member of the die or may be regarded as a horizontal section taken'substantially upon the line 3-`3` upon Fig. l'in the direction indicated;

Fig. 4 is a sectional View through the femaledie taken upon the line -4-4upon` Fig. 2 lin the direction indicated;

y Fig. 5 is a sectional View taken substantially upon the line 5-5 upon Fig. 3;

Figli is a partial View in vertical section taken substantially' upon the line 6 6 upon Fig. 2 in the .direction indicated;

Fig. Tis a sectional view through the improved forming die illustrating it in its fully closed position;

Fig. 8 is a View in side elevation of the die illustrating the parts after the die has started tov open and after a stamping has'been formed; and Fig. 9 is a perspective view of the completed formedstamping which is v4typical of the type of work that maybe v*performed with the improved forming die.

vl`-..eferring to `the accompanying drawings' wherein similar reference characters designate' similar parts throughout, the improved die will' be described in connection with the forming ofA an article from a stamping toproduce an article such as that illustrated in'Fig. 9 although it will be appreciated by those `skilled inthe art" thatthe die is' in no way restricted to the forma-f tion of vsuch articles and mayV be modified to'I form any Itype of article wherein portions of -a stampingor blank of Vsheet metaly are to be bent relatively to other porti-ons. v

or blank lis initiallycut .orshaped to provide the top It, the side II, and two ends, I3 and Handr may have the aperture II stamped therein.

`The'irnproved dieL consists of .a base I5 for the punch or male member.

l The punch or malev member indicated at IG-has a boss I1 on its yupper surfacei adapted to enter the hole II and a guide f strip I8 against which the Vedge .I9 of the stamp-fA ing'orblank'sadapted to nt soas to.-positve1yV position the blankcr stamping on the punch or male die. Other suitable means may be employed on the male die to positively locate the stamping thereon so that it will not have its position disturbed with respect thereto. In the forming of the article illustrated in Fig. 9 only three sides of the blank are to be bent downwardly with respect to the top I and consequently the edge I9 may be utilized to abut the guide strip I8. The three sides indicated by the side I2 and the ends I3 and I4 are to be at exactly right angles to the plane of the top I0. Virtually all metals utilized for this type of-.fwork possess some inherent spring back so that if the sides and ends were merely bent downwardly by the female die to 'a position at right angles to the top l0 on release of the die these portions would spring out wardly to some extent and would not retain their positions at right angles to the top I0. To make correction for this, one side and two ends of the punch or male die I6 are undercut as indicated at 20, the degree of undercut being dependent upon the amount of spring back that is inherently possessed by the metal of the stamping. Thus if the metal of the stamping has a great amount of inherent resiliency the undercut at 20 may have to be severe. On the other hand if the blank or stamping is not extremely springy the degree of undercut will be lessened to compensate therefor so that when the die is opened and the sides of the stamping spring back they will spring into a position at exactly right angles to the top I0. Manifestly if the sides of the stamping represented by the side I2 and the ends I3 and I4 are intended t0 be arranged at other than right angles to the top i0 the sides of the male die are so formed as to allow for the spring back and thus enable these sides to assume their'intended positions with respect to the body of the stamping when the forming die is opened and spring back is allowed to occur. The punch or male member is secured to the base I in any suitable manner such as by bolts 2I and the base member may or may not be equipped with guide posts 22.

The female membervof the die consists of a base 23 equipped with a shank 24 by which it may be attached to a press. The female die indicated at 25 is secured to the b'ase 23 and has an indenture or recess generally indicated at 2B formed therein. The top portion of this recess indicated at 21 is shaped to accommodate a pressure pad or floater 28 to which a bolt 29 is secured that slidably extends through the top of the female die 25, the base 23, and the bottom of the shank 24. A compression spring 3|!` is disposedI about this bolt and urges the pressure pad into its lowermost position. Guide studs 3l may be secured to the pressure pad and are receivable in l apertures 32 in the top of the female die and in the bottom of the base 23. The bottom surface ofthe pressure pad may be shaped to partially receive the boss I1 and any guide pins such as those indicated at 33 on the guide strip I8. The pressure pad or floater is adapted to engage the stamping or blank S positioned on the male die and to press itrdownwardly thereon and to continue to apply pressure to the stamping as the female die descends.. In plan it conforms generally to the plan of the male die. p

IThe lower portion of the recess or indenture 26 is enlarged to accommodate a head 34 and a backing therefor indicated at 35. This backing is formed of a readily compressible material such as rubber neoprene or the like. The head 34 has an aperture therethrough indicated at 36 which closelyconformsto the shape. of the lpunch or male die. Thus the internal dimensions of the aperture 36 are substantially equal to the external dimensions 0f the top of the punch I6 plus the thicknesses of the metal of the stamping S that is to be formed. Usually a very small amount of additional clearance is allowed this being in the neighborhood of one to three thousandths of an inch ordinarily. There is a small clearance indicated at 3'! between the external edges of the head and the interior of the female die. Bolts 38 connect the head through the compressible material 35 to the female die 25` There are small clearances indicated at 39 between the bolts and the head 34 so that a small amount of lateral movement in any direction is permitted of the head 34 with respect to the female die. This lateral movement need not be great and frequently need not be more than one to three thousandths of an inch. The female die 25 and its base 23 have apertures therein to receive the guide posts 22 when these guide posts are employed.

The operation of the improved forming die is as follows: When the stamping or blank S has been positioned on top of the male die or punch I6 the female die is caused to descend and the pressure plate or floater 28 rst engages the blank or stamping and presses it firmly against the punch. As the female die continues to descend the sides of the head 34 engage the projecting portions I2,` I3 and I4 of the blank and bend these downwardly. Usually the bottom edges of theV head 34 surrounding the aperture 36 are slightly rounded to facilitate this bending and to avoid shearing action. Finally as the female die descends, the head 34 passes entirely over the blank or stamping S and engages the base I5 of the male die assuming a position as illustrated in Fig. 7. In this position the head which initially protruded from the female die 25 is forced upwardly therein and highly compresses the compressible rubber like material 35 causing it to be squeezed laterally. E'Xternally there is adequate clearance between the rubber like material 35 and the interior of the female die so that this material may be squeezed outwardly without danger of rupturing the female die. The rubber like material 35 is also squeezed inwardly as illustrated on Fig. 'I

l'and thus applies considerable pressure to rthe downwardly bent sides of the stamping pressing them inwardly into firm engagement with the undercut sides 20 of the punch. When the female die is lifted the pressure on the rubber like material is released and this material returns to its normal position as illustrated in Figs. 4 and 5 and the head 34 is withdrawn over the stamping on the male die. As the material springs back from the undercut sides 2i) it will spring into a position exactly at right angles to the top I0 or into the intended position with respect thereto.

It is to be observed that the small clearances 31 between the bolts 38 and the head 34 provides a small floating movement of the head with respect to the female die and with respect to small amount of clearance is permissible andthe A floating or self-centering action of the heat 3l Veven though very small will ordinarily adequately take care of any difficulties in this regard.

The bases I5 and 23 and the female die 25 may be formed of any strong inexpensive material. I nd that Masonite is highly suitable for this purpose. Likewise the punch 20 and the head 34 may be formed of any strong homogeneous and inexpensive material that may be suitably employed for forming stampings.

It will be appreciated from the above described construction that forming dies of this character may be very easily and quickly constructed and assembled together. Frequently the same bases may be employed with a number of different punches or male dies and with a number of diierent female dies and their heads, it being merely necessary to substitute different dies on the bases.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. A die apparatus comprising a male die or punch, a base to which the punch is xedly secured, the base extending outwardly of the male die or punch, the male die or punch being undercut and adapted to have a piece of work positioned thereon, a female die including a body adapted to be moved toward the male die, the body having a recess, a, pad of readily compressible material receivable in the recess and having its outer edges spaced from the walls of the recess to allow the pad to expand toward the walls, a head receivable in the recess and suspended from the body by bolts which slidably extend through the head and pad and which are fixedly secured to the body, the head being normally disposed at least partially out of the recess so as to contact the base prior to the body, the head and pad being apertured to fit around the male die when the female die is moved toward the male die, the head being adapted to contact the base after bending the work to compress the pad to permit the pad to bend the already bent portions of the work into the undercut portions of the male die.

2. A die apparatus comprising a male die or punch, a base to which the punch is xedly secured, the base extending outwardly of the male die or punch, the male die or punch being undercut and adapted to have a piece of work positioned thereon, a female die including a body adapted to be moved toward the male die, the body having a recess, a pad of readily compressible material receivable in the recess and having its outer edges spaced from the Walls of the recess to allow the pad to expand toward the walls, a head receivable in the recess and suspended from the body by bolts which slidably extend through the head and pad and which are xedly secured to the body, the head being normally disposed at least partially out of the recess so as to contact the base prior to the body, there being clearance between the bolts and head to allow limited lateral movement of the head to permit the head to center itself on the male die, the head and pad being apertured to t around the male die when the female die is moved toward the male die, the head being adapted to contact the base after bending the Work to compress the pad to permit the pad to bend the already bent portions of the work into the undercut portions of the male die.

3. A die apparatus comprising a male die or punch, a base to which the punch is xedly secured, the base extending outwardly of the male die or punch, the male die or punch being undercut and adapted to have a piece of work positioned thereon, a female die including a body adapted to be moved toward the male die, means on the body contacting the work as the body is moved toward the male die to clamp the work on the male die, the body having a recess, a pad of readily compressible material receivable in the recess and having its outer` edges spaced from the walls of the recess to allow the pad to expand toward the walls, a, head receivable in the recess and suspended from the body by bolts which slidably extend through the head and pad and which are fixedly secured to the body, the head being normally disposed at least partially out of the recess so as to contact the base prior to the body, the head and pad being apertured to t around the male die when the female die is moved toward the male die, the head being adapted to contact the base after bending the work to compress the pad to permit the pad to bend the already bent portions of the work into the undercut portions of the male die.

4. A die apparatus comprising a male die or punch, a base to which the punch is xedly secured, the base extending outwardly of the male die or punch, the male die or punch being undercut and adapted to have a piece of work positioned thereon, a female die including a body adapted to be moved toward the male die, means on the body contacting the work as the body is moved toward the male die to clamp the work on the male die, the body having a recess, a pad of readily compressible material receivable in the recess and having its outer edges spaced from the walls of the recess to allow the pad to eX- pand toward the walls, a head receivable in the recess and suspended from the body by bolts which slidably extend through the head and pad and which are fxedly secured to the body, the head and pad being apertured to t around the male die or punch when the female die is moved toward the male die, the head being normally disposed at least partially out of the recess so as to contact the base prior to the body, there being clearance between the bolts and the head to a1- low limited lateral movement of the head to permit the head to center itself on the male die, the head being adapted to contact the base after bending the work to compress the pad to permit the pad to bend the already bent portions of the work 'into the undercut portions of the male die.

CARL LEDEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,534,698 Gansert et al Apr. 21, 1925 2,132,002 Hight Oct. 4, 1938 2,244,847 Oeckel et al June 10, 1941 2,248,786 Rowe et al July 8, 1941 2,342,858 Hansen Feb. 28, 1944 2,368,717 Marschner Feb. 6, 1945 2,400,004 Jager May 7, 1946 FOREIGN PATENTS Number Country Date 3,504 Great Britain of 1890 795,359 France Jan. 6. 1936 

